A corpus of 12,151 open research problems and 200 formally graded ones found closed-book rediscovery rare, at most 7 of 40 solved problems
AspireAI community · arXiv (cs.CL)
LLMs are increasingly used for research-level problem solving, but there has been no broad corpus of such problems and no way to grade a formal proof against one. OpenFrontiers combines a structured corpus of 12,151 open research problems, recording statements, context and progress, with a retrospective benchmark of 200 recently resolved mathematics problems, 110 resolved in 2026 and 90 still open, each carrying a Lean 4 statement checked by automated probes and two independent reviews, with a quality-filtered HQ-50 subset. Seven LLM agents were graded on formal proofs by two independent checkers in an isolated sandbox under closed-book, frozen-retrieval and live-web conditions, and closed-book rediscovery was rare, at most 7 of the 40 resolved problems, while live-web success mostly reflected retrieval of already-published solutions. The limitation: the benchmark is mathematics-only and retrospective, so it measures recovery of known proofs rather than whether agents can make genuinely new progress on the 90 open problems.
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